Method, system and non-transitory computer-readable recording medium for supporting object control by using a 2D camera

ABSTRACT

According to one aspect of the present invention, there is provided a method for assisting object control using a two-dimensional camera, comprising the steps of: acquiring a two-dimensional image of a user&#39;s body from a two-dimensional camera; and determining a control target area with reference to a candidate target area specified on the basis of two-dimensional relative coordinate points respectively corresponding to a first body part and a second body part of the user in the two-dimensional image, wherein the candidate target area and the control target area are determined on a reference surface established with respect to the two-dimensional camera.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation application of Patent CooperationTreaty (PCT) International Application No. PCT/KR2020/003063 filed onMar. 4, 2020, which claims priority to Korean Patent Application No.10-2019-0027623 filed on Mar. 11, 2019. The entire contents of PCTInternational Application No. PCT/KR2020/003063 and Korean PatentApplication No. 10-2019-0027623 are hereby incorporated by reference.

This application is filed with the support of Korean Ministry of Scienceand ICT under Project No. A0712-20-1024 awarded by National IT IndustryPromotion Agency (NIPA) of Republic of Korea.

FIELD OF THE INVENTION

The present invention relates to a method, system, and non-transitorycomputer-readable recording medium for assisting object control using atwo-dimensional camera.

BACKGROUND

In recent years, as interest in augmented reality (AR) or virtualreality (VR) is increasing and research and development in relatedtechnical fields are actively carried out, a variety of techniques forcontrolling an object using a body part of a user have been introduced.

As an example of related conventional techniques, Korean Laid-OpenPatent Publication No. 10-2012-126508 discloses a method for recognizinga touch in a virtual touch device without using a pointer, wherein thevirtual touch device comprises: an image acquisition unit composed oftwo or more image sensors disposed at different positions and configuredto photograph a user's body in front of a display surface; a spatialcoordinate calculation unit configured to calculate three-dimensionalcoordinate data of the user's body using an image received from theimage acquisition unit; a touch position calculation unit configured touse first and second spatial coordinates received from the spatialcoordinate calculation unit to calculate coordinate data of a contactpoint where a straight line connecting the first and second spatialcoordinates meets the display surface; and a virtual touch processingunit configured to generate a command code for performing an operationcorresponding to the contact point coordinate data received from thetouch position calculation unit and input the command code to a maincontrol unit of an electronic apparatus, and wherein the methodcomprises the steps of: (a) processing three-dimensional coordinate data(X1, Y1, Z1) of a fingertip and three-dimensional coordinate data (X2,Y2, Z2) of a center point of an eye to detect a contact point A of theeye, a fingertip point B, and a display surface C, respectively; (b)calculating at least one of a depth change, a trajectory change, aholding time, and a change rate of the detected fingertip point; and (c)causing the electronic apparatus to be operated or causing an areacorresponding to a touched part of a touch panel to be selected, on thebasis of the at least one of the depth change, the trajectory change,the holding time, and the change rate of the fingertip point.

According to the techniques introduced so far as well as theabove-described conventional technique, a process of acquiringthree-dimensional coordinates of a user's body parts using athree-dimensional camera is essentially required in order to select orcontrol an object. However, the three-dimensional camera is not onlyexpensive but also causes a lot of delays in the course of processingthree-dimensional data. A central processing unit (CPU) or the like withhigher performance is required to address the delays, resulting in ahigher overall price.

In this connection, the inventor(s) present a novel and inventivetechnique for assisting a user to efficiently and accurately select orcontrol an intended target object using only a conventionaltwo-dimensional camera, without a three-dimensional camera.

SUMMARY OF THE INVENTION

One object of the present invention is to solve all the above-describedproblems in the prior art.

Another object of the invention is to accurately determine a controltarget area that meets a user's intention using only informationacquired through a two-dimensional camera, without using a precisesensing means such as a three-dimensional camera.

Yet another object of the invention is to efficiently determine acontrol target area using less resources.

The representative configurations of the invention to achieve the aboveobjects are described below.

According to one aspect of the invention, there is provided a method forassisting object control using a two-dimensional camera, comprising thesteps of: acquiring a two-dimensional image of a user's body from atwo-dimensional camera; and determining a control target area withreference to a candidate target area specified on the basis oftwo-dimensional relative coordinate points respectively corresponding toa first body part and a second body part of the user in thetwo-dimensional image, wherein the candidate target area and the controltarget area are determined on a reference surface established withrespect to the two-dimensional camera.

According to another aspect of the invention, there is provided a systemfor assisting object control using a two-dimensional camera, comprising:an image acquisition unit configured to acquire a two-dimensional imageof a user's body from a two-dimensional camera; and a control targetarea determination unit configured to determine a control target areawith reference to a candidate target area specified on the basis oftwo-dimensional relative coordinate points respectively corresponding toa first body part and a second body part of the user in thetwo-dimensional image, wherein the candidate target area and the controltarget area are determined on a reference surface established withrespect to the two-dimensional camera.

In addition, there are further provided other methods and systems toimplement the invention, as well as non-transitory computer-readablerecording media having stored thereon computer programs for executingthe methods.

According to the invention, it is possible to accurately determine acontrol target area that meets a user's intention using only informationacquired through a two-dimensional camera, without using a precisesensing means such as a three-dimensional camera.

According to the invention, it is possible to efficiently determine acontrol target area using less resources.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 specifically shows the internal configuration of an objectcontrol assistance system according to one embodiment of the invention.

FIG. 2 illustratively shows how to determine a candidate target areausing a two-dimensional camera according to one embodiment of theinvention.

FIG. 3 illustratively shows how to determine a candidate target areausing a two-dimensional camera according to one embodiment of theinvention.

FIG. 4 illustratively shows how to determine a control target areaaccording to a first embodiment of the invention.

FIG. 5A illustratively shows how to determine a control target areaaccording to another embodiment of the invention.

FIG. 5B illustratively shows how to determine a control target areaaccording to another embodiment of the invention.

FIG. 5C illustratively shows how to determine a control target areaaccording to another embodiment of the invention.

FIG. 6 illustratively shows a situation in which a control target areaintended by a user is determined using two or more two-dimensionalimages respectively acquired from two or more two-dimensional camerasaccording to another embodiment of the invention.

DETAILED DESCRIPTION

In the following detailed description of the present invention,references are made to the accompanying drawings that show, by way ofillustration, specific embodiments in which the invention may bepracticed. These embodiments are described in sufficient detail toenable those skilled in the art to practice the invention. It is to beunderstood that the various embodiments of the invention, althoughdifferent from each other, are not necessarily mutually exclusive. Forexample, specific shapes, structures and characteristics describedherein may be implemented as modified from one embodiment to anotherwithout departing from the spirit and scope of the invention.Furthermore, it shall be understood that the positions or arrangementsof individual elements within each of the embodiments may also bemodified without departing from the spirit and scope of the invention.Therefore, the following detailed description is not to be taken in alimiting sense, and the scope of the invention is to be taken asencompassing the scope of the appended claims and all equivalentsthereof. In the drawings, like reference numerals refer to the same orsimilar elements throughout the several views.

Hereinafter, various preferred embodiments of the present invention willbe described in detail with reference to the accompanying drawings toenable those skilled in the art to easily implement the invention.

Configuration of the Entire System

The entire system according to one embodiment of the invention maycomprise a communication network, an object control assistance system100, and a two-dimensional camera.

First, the communication network according to one embodiment of theinvention may be implemented regardless of communication modality suchas wired and wireless communications, and may be constructed from avariety of communication networks such as local area networks (LANs),metropolitan area networks (MANs), and wide area networks (WANs).Preferably, the communication network described herein may be theInternet or the World Wide Web (WWW). However, the communication networkis not necessarily limited thereto, and may at least partially includeknown wired/wireless data communication networks, known telephonenetworks, or known wired/wireless television communication networks.

For example, the communication network may be a wireless datacommunication network, at least a part of which may be implemented witha conventional communication scheme such as radio frequency (RF)communication, WiFi communication, cellular communication (e.g., LongTerm Evolution (LTE) communication), Bluetooth communication (morespecifically, Bluetooth Low Energy (BLE) communication), infraredcommunication, and ultrasonic communication.

Next, the object control assistance system 100 according to oneembodiment of the invention may be a digital device having a memorymeans and a microprocessor for computing capabilities. The objectcontrol assistance system 100 may be a server system.

According to one embodiment of the invention, the object controlassistance system 100 may be connected to the two-dimensional camera tobe described below via the communication network or a processor (notshown), and may function to acquire a two-dimensional image of a user'sbody from the two-dimensional camera and to determine a control targetarea with reference to a candidate target area specified on the basis oftwo-dimensional relative coordinate points respectively corresponding toa first body part and a second body part of the user in thetwo-dimensional image, wherein the candidate target area and the controltarget area are determined on a reference surface established withrespect to the two-dimensional camera.

Here, the two-dimensional relative coordinate points according to oneembodiment of the invention may be specified in a relative coordinatesystem associated with the two-dimensional camera. For example,according to one embodiment of the invention, a two-dimensionalcoordinate system specified around a lens of the two-dimensional camera(e.g., the lens is centered at (0, 0)) (or around a two-dimensionalimage photographed by the two-dimensional camera) may be specified asthe relative coordinate system in which the two-dimensional relativecoordinate points may be specified.

Further, according to one embodiment of the invention, the body partsmay include a head, eyes, a nose, a mouth, hands, fingertips, fingers,feet, tiptoe, toes, and the like, but are not limited to the foregoingand may be changed to various body parts as long as the objects of theinvention may be achieved.

Furthermore, according to one embodiment of the invention, the controltarget area may be determined on the reference surface established withrespect to the two-dimensional camera. According to one embodiment ofthe invention, the reference surface established with respect to thetwo-dimensional camera may encompass a surface of a predetermined sizethat is established around the two-dimensional camera or positionedadjacent (or within a predetermined distance) to the two-dimensionalcamera. The reference surface may be shaped to be flat or curved, andmay include a display screen, a printed paper sheet, a wall, and thelike.

The configuration and functions of the object control assistance system100 according to the invention will be discussed in more detail below.Meanwhile, although the object control assistance system 100 has beendescribed as above, the above description is illustrative and it will beapparent to those skilled in the art that at least a part of thefunctions or components required for the object control assistancesystem 100 may be implemented or included in an external system (notshown), as necessary.

Next, the two-dimensional camera according to one embodiment of theinvention may communicate with the object control assistance system 100by means of the communication network or a processor, and may functionto acquire the two-dimensional image of the user's body. For example,the two-dimensional camera according to one embodiment of the inventionmay include various types of image sensors, such as a charge coupleddevice (CCD) and a complementary metal oxide semiconductor (CMOS).

Configuration of the Object Control Assistance System

Hereinafter, the internal configuration of the object control assistancesystem 100 crucial for implementing the invention and the functions ofthe respective components thereof will be discussed.

FIG. 1 specifically shows the internal configuration of the objectcontrol assistance system 100 according to one embodiment of theinvention.

As shown in FIG. 1, the object control assistance system 100 accordingto one embodiment of the invention may comprise an image acquisitionunit 110, a control target area determination unit 120, a communicationunit 130, and a control unit 140. According to one embodiment of theinvention, at least some of the image acquisition unit 110, the controltarget area determination unit 120, the communication unit 130, and thecontrol unit 140 may be program modules to communicate with an externalsystem. The program modules may be included in the object controlassistance system 100 in the form of operating systems, applicationprogram modules, and other program modules, while they may be physicallystored in a variety of commonly known storage devices. Further, theprogram modules may also be stored in a remote storage device that maycommunicate with the object control assistance system 100. Meanwhile,such program modules may include, but not limited to, routines,subroutines, programs, objects, components, data structures, and thelike for performing specific tasks or executing specific abstract datatypes as will be described below in accordance with the invention.

First, the image acquisition unit 110 according to one embodiment of theinvention may function to acquire a two-dimensional image of a user'sbody from a two-dimensional camera.

For example, the image acquisition unit 110 according to one embodimentof the invention may acquire a two-dimensional image in which the user'sbody including eyes (e.g., both eyes or a dominant eye) and fingers(e.g., a tip of an index finger) is photographed.

Next, the control target area determination unit 120 according to oneembodiment of the invention may determine a control target area withreference to a candidate target area specified on the basis oftwo-dimensional relative coordinate points respectively corresponding toa first body part and a second body part of the user in thetwo-dimensional image. Here, the control target area determination unit120 according to one embodiment of the invention may determine thecandidate target area and the control target area on a reference surfaceestablished with respect to the two-dimensional camera.

Specifically, according to one embodiment of the invention, thecandidate target area may be specified by a virtual point and a pointwhere the two-dimensional camera is positioned on a virtual referencesurface. A positional relationship between the virtual point and thepoint where the two-dimensional camera is positioned on the virtualreference surface may be specified by a positional relationship betweenthe two-dimensional relative coordinate points respectivelycorresponding to the first and second body parts in the two-dimensionalimage.

FIGS. 2 and 3 illustratively show how to determine a candidate targetarea using a two-dimensional camera according to one embodiment of theinvention.

In the embodiments of FIGS. 2 and 3, the two-dimensional cameraaccording to one embodiment of the invention may be included in anobject display device, and may be positioned adjacent to the objectdisplay device if necessary. In this case, a display screen of theobject display device according to one embodiment of the invention maybe located on a reference surface 300 established with respect to thetwo-dimensional camera, or may have a matching positional relationshipwith the two-dimensional camera.

Further, in the embodiments of FIGS. 2 and 3, it may be assumed thatobjects “a” to “t” are displayed or printed on the display screen of theobject display device. In addition, the objects displayed on the objectdisplay device according to the invention may be not only displayedelectronically but also displayed in various ways such as printing,engraving, and embossing as long as the objects of the invention may beachieved.

Furthermore, in the embodiment of FIGS. 2 and 3, the object displaydevice according to one embodiment of the invention may be connected tothe object control assistance system 100 via the communication networkor a processor, and may function to display an object to be controlledby the user. For example, according to one embodiment of the invention,the object display device may comprise a liquid crystal display (LCD), athin film transistor LCD (TFT LCD), a light emitting diode (LED)display, an organic LED (OLED) display, an active matrix OLED (AMOLED)display, a flexible display, and a three-dimensional display.

First, referring to FIG. 2, the control target area determination unit120 according to one embodiment of the invention may specify an angle205 between a straight line 203 connecting two-dimensional relativecoordinate points of an eye 201 and a fingertip 202 of the userspecified in a two-dimensional image 200 acquired from thetwo-dimensional camera, and a reference line 204 preestablished in thetwo-dimensional image 200. Here, according to one embodiment of theinvention, the reference line 204 preestablished in the two-dimensionalimage 200 may be a horizontal line (or a vertical line) specified by ahorizontal axis (or a vertical axis) of the two-dimensional image 200,or may be a straight line parallel to a straight line connecting botheyes of the user in the two-dimensional image 200.

Next, referring to FIG. 3, the control target area determination unit120 according to one embodiment of the invention may specify a virtualpoint 302 such that an angle 305 formed by a virtual straight line 303,which connects the virtual point 302 and a point 301 where thetwo-dimensional camera is positioned on the reference surface 300established with respect to the two-dimensional camera, and a referenceline 304 is substantially the same as the angle 205 specified in thetwo-dimensional image 200 of FIG. 2, and may specify an area 306surrounding the virtual straight line 303, which connects the virtualpoint 302 and the point 301 where the two-dimensional camera ispositioned on the reference surface 300, as a candidate target area.Here, according to one embodiment of the invention, the reference line304 specified on the reference surface 300 may be a straight lineparallel to the reference line 204 preestablished in the two-dimensionalimage 200, or may be a straight line corresponding to a horizontal axisof the object display device including the two-dimensional camera.

Further, according to one embodiment of the invention, the controltarget area determination unit 120 may determine a control target areathat is judged to meet the user's control intention with reference tothe specified candidate target area.

Specifically, according to one embodiment of the invention, the controltarget area determination unit 120 may determine an area within thespecified candidate target area that is judged to be associated with agesture of the user as the control target area. Here, according to oneembodiment of the invention, the user's gesture may include a gesture ofmoving the first or second body part of the user (e.g., a gesture of theuser moving a fingertip being photographed by the two-dimensional camerain a direction intended by the user).

FIG. 4 illustratively shows how to determine a control target areaaccording to a first embodiment of the invention.

Referring to FIG. 4, in response to detecting a gesture by which thetwo-dimensional relative coordinate point 202 corresponding to theuser's second body part in the two-dimensional image is moved in a lowerleft direction 202′, the control target area determination unit 120according to one embodiment of the invention may determine a partialarea 307 positioned in a relatively lower right direction within thecandidate target area 306 on the reference surface 300 as a controltarget area, and may further determine an object 309 positioned in thecontrol target area 307, among two objects 308 and 309 positioned in thecandidate target area 306, as an object to be controlled (or selected)by the user. That is, according to one embodiment of the invention,since the object “i” 308 and the object “t” 309 are included in thecandidate target area 306 but only the object “t” 309 is included in thecontrol target area 307, the object “t” 309 may be determined as acontrol target object intended by the user.

Meanwhile, according to one embodiment of the invention, the controltarget area determination unit 120 may provide guide information forassisting the user to identify the candidate target area specified bythe object control assistance system 100, and may determine an areajudged to be associated with the user's gesture recognized after theguide information is provided as a control target area.

For example, when the reference surface is established in correspondenceto the object display device, the control target area determination unit120 according to one embodiment of the invention may provide the guideinformation to the user by displaying the candidate target area (or anobject positioned in the candidate target area) with a highlight on theobject display device. Further, the control target area determinationunit 120 according to one embodiment of the invention may determine acontrol target area within the candidate target area by recognizing agesture that the user makes after receiving the guide information inorder to accurately specify a control target area to be controlled bythe user within the candidate target area.

Meanwhile, the communication unit 130 according to one embodiment of theinvention may function to enable data transmission/reception from/to theimage acquisition unit 110 and the control target area determinationunit 120.

Lastly, the control unit 140 according to one embodiment of theinvention may function to control data flow among the image acquisitionunit 110, the control target area determination unit 120, and thecommunication unit 130. That is, the control unit 140 according to theinvention may control data flow into/out of the object controlassistance system 100 or data flow among the respective components ofthe object control assistance system 100, such that the imageacquisition unit 110, the control target area determination unit 120,and the communication unit 130 may carry out their particular functions,respectively.

Meanwhile, according to another embodiment of the invention, the objectcontrol assistance system 100 may determine a control target area judgedto be intended by the user on the basis of information acquired from twoor more two-dimensional images of the user's body, which are acquiredfrom two or more two-dimensional cameras, respectively.

Specifically, the object control assistance system 100 according toanother embodiment of the invention may acquire a first two-dimensionalimage in which the user's body is photographed from a firsttwo-dimensional camera, and a second two-dimensional image in which theuser's body is photographed from a second two-dimensional camera.

Next, the object control assistance system 100 according to anotherembodiment of the invention may determine a control target area withreference to a first candidate target area specified on the basis oftwo-dimensional relative coordinate points respectively corresponding toa first body part and a second body part of the user in the firsttwo-dimensional image, and a second candidate target area specified onthe basis of two-dimensional relative coordinate points respectivelycorresponding to the first and second body parts of the user in thesecond two-dimensional image. For example, the object control assistancesystem 100 according to another embodiment of the invention maydetermine an area common to the first candidate target area and thesecond candidate target area as the control target area. Here, accordingto another embodiment of the invention, the control target area may bedetermined on a reference surface established with respect to the firstand second two-dimensional cameras.

FIGS. 5A to 5C illustratively show how to determine a control targetarea according to another embodiment of the invention.

First, referring to FIG. 5A, the object control assistance system 100according to another embodiment of the invention may specify a firstangle 515 between a straight line 513 connecting two-dimensionalrelative coordinate points of an eye 511 and a fingertip 512 of a userspecified in a first two-dimensional image 510 acquired from a firsttwo-dimensional camera, and a reference line 514 preestablished in thefirst two-dimensional image 510.

Next, referring to FIG. 5B, the object control assistance system 100according to another embodiment of the invention may specify a secondangle 525 between a straight line 523 connecting two-dimensionalrelative coordinate points of an eye 521 and a fingertip 522 of the userspecified in a second two-dimensional image 520 acquired from a secondtwo-dimensional camera, and a reference line 524 preestablished in thesecond two-dimensional image 520.

Next, referring to FIG. 5C, the object control assistance system 100according to another embodiment of the invention may specify a firstvirtual point such that an angle 533 formed by a first virtual straightline 532, which connects the first virtual point and a point 531 wherethe first two-dimensional camera is positioned on a reference surface530 established with respect to the first and second two-dimensionalcameras, and a first reference line is substantially the same as thefirst angle 515 specified in the first two-dimensional image 510 of FIG.5A, and may specify an area 534 surrounding the first virtual straightline 532, which connects the first virtual point and the point 531 wherethe first two-dimensional camera is positioned on the reference surface530, as a first candidate target area. Here, according to anotherembodiment of the invention, the first reference line specified on thereference surface 530 may be a straight line parallel to the referenceline 514 preestablished in the first two-dimensional image 510, or maybe a straight line corresponding to a horizontal axis of the objectdisplay device.

Referring further to FIG. 5C, the object control assistance system 100according to another embodiment of the invention may specify a secondvirtual point such that an angle 537 formed by a second virtual straightline 536, which connects the second virtual point and a point 535 wherethe second two-dimensional camera is positioned on the reference surface530, and a second reference line is substantially the same as the secondangle 525 specified in the second two-dimensional image 520 of FIG. 5B,and may specify an area 538 surrounding the second virtual straight line536, which connects the second virtual point and the point 535 where thesecond two-dimensional camera is positioned on the reference surface530, as a second candidate target area. Here, according to anotherembodiment of the invention, the second reference line specified on thereference surface 530 may be a straight line parallel to the referenceline 524 preestablished in the second two-dimensional image 520, or maybe a straight line corresponding to the horizontal axis of the objectdisplay device.

Referring further to FIG. 5C, the object control assistance system 100according to another embodiment of the invention may determine an area539 on the reference surface 530 that is common to the first candidatetarget area 534 and the second candidate target area 538 as a controltarget area, and may further determine an object positioned in thecontrol target area 539, among objects displayed on the object displaydevice, as an object to be controlled (or selected) by the user.

That is, according to another embodiment of the invention, the user'scontrol intention may be recognized more accurately and precisely usingtwo or more two-dimensional images respectively acquired from two ormore two-dimensional cameras.

FIG. 6 illustratively shows a situation in which a control target areaintended by a user is determined using two or more two-dimensionalimages respectively acquired from two or more two-dimensional camerasaccording to another embodiment of the invention.

Referring to FIG. 6, the object control assistance system 100 accordingto another embodiment of the invention may use information acquired fromtwo or more two-dimensional images, which are respectively acquiredthrough two or more two-dimensional cameras 601 and 602 provided in amobile device 600, to determine an icon 603 displayed on a displayscreen of the mobile device 600, a specific point 604 in an electronicmap displayed on the display screen of the mobile device 600, any point605 outside the display screen of the mobile device 600, or the like asa control target area intended by the user.

The embodiments according to the invention as described above may beimplemented in the form of program instructions that can be executed byvarious computer components, and may be stored on a computer-readablerecording medium. The computer-readable recording medium may includeprogram instructions, data files, and data structures, separately or incombination. The program instructions stored on the computer-readablerecording medium may be specially designed and configured for thepresent invention, or may also be known and available to those skilledin the computer software field. Examples of the computer-readablerecording medium include the following: magnetic media such as harddisks, floppy disks and magnetic tapes; optical media such as compactdisk-read only memory (CD-ROM) and digital versatile disks (DVDs);magneto-optical media such as floptical disks; and hardware devices suchas read-only memory (ROM), random access memory (RAM) and flash memory,which are specially configured to store and execute programinstructions. Examples of the program instructions include not onlymachine language codes created by a compiler, but also high-levellanguage codes that can be executed by a computer using an interpreter.The above hardware devices may be changed to one or more softwaremodules to perform the processes of the present invention, and viceversa.

Although the present invention has been described above in terms ofspecific items such as detailed elements as well as the limitedembodiments and the drawings, they are only provided to help moregeneral understanding of the invention, and the present invention is notlimited to the above embodiments. It will be appreciated by thoseskilled in the art to which the present invention pertains that variousmodifications and changes may be made from the above description.

Therefore, the spirit of the present invention shall not be limited tothe above-described embodiments, and the entire scope of the appendedclaims and their equivalents will fall within the scope and spirit ofthe invention.

What is claimed is:
 1. A system for assisting object control using atwo-dimensional camera, comprising: an image acquisition unit configuredto acquire a two-dimensional image of a user's body from atwo-dimensional camera; and a control target area determination unitconfigured to determine a control target area with reference to acandidate target area specified on the basis of two-dimensional relativecoordinate points respectively corresponding to a first body part and asecond body part of the user in the two-dimensional image, wherein thecandidate target area and the control target area are determined on areference surface established with respect to the two-dimensionalcamera, wherein the candidate target area is specified on the basis of avirtual line connecting a virtual point and a point where thetwo-dimensional camera is positioned on the reference surface, whereinthe virtual point is specified with reference to an angle between a lineconnecting the two-dimensional relative coordinate points respectivelycorresponding to the first and second body parts in the two-dimensionalimage, and a reference line established in the two-dimensional image,and wherein the control target area determination unit is configured todetermine an object included in the control target area, among objectsincluded in the candidate target area, as an object to be controlled bythe user.
 2. A method for assisting object control using atwo-dimensional camera, comprising the steps of: acquiring atwo-dimensional image of a user's body from a two-dimensional camera;and determining a control target area with reference to a candidatetarget area specified on the basis of two-dimensional relativecoordinate points respectively corresponding to a first body part and asecond body part of the user in the two-dimensional image, wherein thecandidate target area and the control target area are determined on areference surface established with respect to the two-dimensionalcamera, wherein the candidate target area is specified on the basis of avirtual line connecting a virtual point and a point where thetwo-dimensional camera is positioned on the reference surface, whereinthe virtual point is specified with reference to an angle between a lineconnecting the two-dimensional relative coordinate points respectivelycorresponding to the first and second body parts in the two-dimensionalimage, and a reference line established in the two-dimensional image,and wherein in the determining step, an object included in the controltarget area, among objects included in the candidate target area, isdetermined as an object to be controlled by the user.
 3. The method ofclaim 2, wherein the two-dimensional relative coordinate points arespecified in a relative coordinate system associated with thetwo-dimensional camera.
 4. The method of claim 2, wherein in thedetermining step, an area within the candidate target area that isjudged to be associated with a gesture of the user is determined as thecontrol target area.
 5. The method of claim 4, wherein the gestureincludes a gesture of the user moving the first body part or the secondbody part.
 6. The method of claim 4, wherein the determining stepcomprises the steps of: providing guide information for assisting theuser to identify the candidate target area; and determining an areajudged to be associated with the user's gesture recognized after theguide information is provided as the control target area.
 7. The methodof claim 2, wherein in the acquiring step, a first two-dimensional imageof the user's body is acquired from a first two-dimensional camera, anda second two-dimensional image of the user's body is acquired from asecond two-dimensional camera, wherein in the determining step, thecontrol target area is determined with reference to a first candidatetarget area specified on the basis of two-dimensional relativecoordinate points respectively corresponding to the first and secondbody parts of the user in the first two-dimensional image, and a secondcandidate target area specified on the basis of two-dimensional relativecoordinate points respectively corresponding to the first and secondbody parts of the user in the second two-dimensional image, and whereinthe first candidate target area, the second candidate target area, andthe control target area are determined on a reference surfaceestablished with respect to the first and second two-dimensionalcameras.
 8. The method of claim 7, wherein in the determining step, anarea common to the first candidate target area and the second candidatetarget area is determined as the control target area.
 9. Anon-transitory computer-readable recording medium having stored thereona computer program for executing the method of claim 2.